1. Field of the Invention:
The invention relates to fluid distributors. More specifically, the invention relates to a rotary valve which sequentially connects a plurality of fluid inlet lines to a single fluid outlet line.
2. Description of the Prior Art:
During the handling of fluids in many types of work, it is necessary to periodically distribute a plurality of different fluids to a common point; and, in some instances, it is desirable to return each fluid separately to its respective container. In the processing and staining of histologic tissue sections, it is desirable to sequentially transfer each of the various treating fluids from its respective fluid container to a processing chamber and to return each such fluid to its container before introduction of the next treating fluid. In this regard, U.S. Pat. No. 3,892,197 discloses a rotary valve made of a rotatable plate and a fixed plate for use in a light microscopy tissue processor. U.S. Pat. Nos. 2,959,151 and 3,400,726 also describe apparatus for treating biological preparations having rotary distributor elements useful in the distrubution of the treating fluids. It is the purpose of the present invention to provide a reliable leakproof construction and a simple start/stop switch mechanism for a rotary valve of the general type disclosed in U.S. Pat. No. 3,892,197.
Fluid distributors having rotary distributor discs have been in use for years in the fuel injection systems of internal combustion engines as illustrated in U.S. Pat. No. 3,079,948. Such fluid distributors are designed to provide incremental distribution of fluid from a single source to individual outlets. U.S. Pat. No. 3,124,162 discloses a fluid valve of more general application designed to supply fluid to a plurality of fluid outlets from a single main. Other patents broadly teaching fluid distributors incorporating rotary distribution elements include U.S. Pat. Nos. 3,076,478 and 3,319,655.
It is believed that the prior art fails to teach a simple, reliable and substantially leakproof rotary valve adapted for use in automatic programmed fluid transfer devices.